I just recently got my S-12, and the first thing I did was take off the muzzle attachment, put on an adjustable stock with pistol grip, and put the factory mag away for the time being. Got a couple of 10 round mags and took it out to play with it. New FCG parts are on my birthday list, so in a couple weeks I'll do the conversion and not have to worry about using the factory mag in the compliance count.